Single-Battery Preamp 3 PUBLIC

Guitar preamp powered by a single 9-volt battery, with two gain stages, shunt-type Schottky-diode fuzz, and 2-band tone.

Guitar preamp powered by a single 9V battery. Features two stages of gain, a Schottky-diode shunt-type diode array, and 2-band Fender-style tone-stack. Controls Include: Input Attenuation enable switch (Attenuate or Direct), Attenuation control, Input Gain, Direct Send, Fuzz Enable switch, Fuzz symmetry switches, Fuzz Depth, Bass, Treble, Output Gain, and Volume. Range is 50 Hz to 20 kHz. Maximum Gain = +11 dBV @ 1 kHz with all controls at 50%. Suitable for 6/7-string guitar (not recommended for 8-string guitar or bass-guitar). Modest gain as shown. For gain in "boost" category (+18 dBV), make the Gain pot values 250k. For gain in "overdrive" category (+24 dBV), make the Gain pots 500k. The circuit is meant for stomp-box projects, but the battery can be replaced by a regulated single-polarity DC supply providing +9VDC or +12VDC or +15VDC at >= 20 mA of current. And though simulator verified, treat it as experimental. Breadboard test it before committing to a soldered build.